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Wolf  GL 《Radiology》1986,159(2):557-558
The advantages of the new, safer, but more expensive iodinated contrast agents are discussed, and opinions on which patient groups should receive the agents are presented.  相似文献   
3.
高建华  文广伶  张其楷 《药学学报》1990,25(12):891-897
研究了强效抗胆碱药dl-3-(2-苯基-2-环戊基-2-羟基-乙氧基)-奎宁环烷的四个光学异构体的两种不对称合成方法,用HPLC检测了异构体含量,讨论了构效关系。  相似文献   
4.
McLellan  GL; Scalapino  MC 《Radiology》1988,169(1):264-265
A modified technique for catheterization of the pulmonary artery was developed. It involves the passage of a tapered, movable-core, J-tipped guide wire across the right ventricle into the pulmonary artery followed by the advancement of a straightened Grollman pigtail catheter. The technique was successful in 34 of 34 pulmonary artery catheterizations. The method avoids prolonged catheter manipulation within the right ventricle. In addition, since the catheter does not cross the tricuspid valve until the guide wire has been advanced, the occasional complication of the pigtail "hooking" on a tricuspid valve leaflet or chordae tendineae during catheter withdrawal and manipulation is prevented.  相似文献   
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乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
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Chitosan, a derivative of the bio-polysaccharide chitin, has shown promise as a bioactive material for implant, tissue engineering and drug-delivery applications. The aim of this study was to evaluate the contact angle, protein adsorption and osteoblast precursor cell attachment to chitosan coatings bonded to titanium. Rough ground titanium (Ti) coupons were solution cast and bonded to 91.2% de-acetylated chitosan (1 wt% chitosan in 0.2% acetic acid) coatings via silane reactions. Non-coated Ti was used as controls. Samples were sterilized by ethylene oxide gas prior to experiments. Contact angles on all surfaces were measured using water. 5 x 10(4) cells/ml of ATCC CRL 1486 human embryonic palatal mesenchyme (HEPM) cells, an osteoblast precursor cell line, were used for the cell attachment study. SEM evaluations were performed on cells attached to all surfaces. Contact angles and cell attachment on all surfaces were statistically analyzed using ANOVA. The chitosan-coated surfaces (76.4 +/- 5.1 degrees) exhibited a significantly greater contact angle compared to control Ti surfaces (32.2 +/- 6.1 degrees). Similarly, chitosan-coated surfaces exhibited significantly greater (P < 0.001) albumin adsorption, fibronectin adsorption and cell attachment, as compared to the control Ti surfaces. Coating chitosan on Ti surfaces decreased the wettability of the Ti, but increased protein adsorption and cell attachment. Increased protein absorption and cell attachment on the chitosan-coated Ti may be of benefit in enhancing osseointegration of implant devices.  相似文献   
9.
BACKGROUND: We had the impression that, although our renal transplant recipients with polycystic kidney disease (PKD) had excellent long-term renal graft function, they had an increased incidence of postoperative gastrointestinal (GI) complications. METHODS: Over a 10-year period (1987 through 1996), 1467 renal transplants were performed in 1417 patients; 145 of these transplants involved PKD recipients. In the PKD group, 18 patients (12.4%) developed a posttransplant complication necessitating GI surgery (PKD-GI), an incidence twice that in the non-PKD recipients (73 patients or 6.2%, non-PKD-GI). RESULTS: PKD and non-PKD recipients displayed no significant difference in mortality. The PKD patients had better long-term renal graft survival than the non-PKD patients (P=0.08). There was no difference in mortality (P>0.6) or renal graft survival (P>0.6) between the PKD-GI and PKD-non-GI groups. The PKD-GI group had no increased mortality over the non-PKD-GI patients (P>0.6), despite a higher incidence of GI surgical complications in the PKD group versus the non-PKD group (overall: 12.4 vs. 6.2%, P<0.01; within 90 days of transplant: 7.6 vs. 3.3%, P<0.02) and a greater propensity for small and large bowel complications (overall: 9.0 vs. 2.6%; P< 0.001; less than 90 days: 6.9 vs. 2.0%, P<0.002). The PKD-GI recipients tended toward less long-term graft loss than their non-PKD-GI counterparts (11.1 vs. 27.4%; P=.22). The PKD-GI recipients suffered no acute rejection episodes within 90 days after their GI operation versus 11 of 73 non-PKD-GI recipients (O vs. 15.1%; P=0.075). CONCLUSIONS: PKD recipients of renal grafts should be watched closely early after transplant because of their increased risk of GI complications. These complications resulted in no increase in mortality or graft loss compared to non-PKD recipients with GI complications despite the PKD group's higher incidence of bowel perforation and increased age at time of transplant.  相似文献   
10.
  • 1 Autoradiographic binding studies have shown that the AT1 receptor is the predominant angiotensin II (AngII) receptor subtype in the central nervous system (CNS). Major sites of AT1 receptors are the lamina terminalis, hypothalamic paraventricular nucleus, the lateral parabrachial nucleus, rostral and caudal ventrolateral medulla, nucleus of the solitary tract and the intermediolateral cell column of the thoraco-lumbar spinal cord.
  • 2 While there are differences between species, AT2 receptors are found mainly in the cerebellum, inferior olive and locus coeruleus of the rat.
  • 3 Circulating AngII acts on AT1 receptors in the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) to stimulate neurons that may have a role in initiating water drinking.
  • 4 Centrally administered AngII may act on AT1 receptors in the median preoptic nucleus and elsewhere to induce drinking, sodium appetite, a sympathetic vasoconstrictor response and vasopressin secretion.
  • 5 Recent evidence shows that centrally administered AT1 antagonists inhibit dipsogenic, natriuretic, pressor and vasopressin secretory responses to intracerebroventricular infusion of hypertonic saline. This suggests that an angiotensinergic neural pathway has a role in osmoregulatory responses.
  • 6 Central angiotensinergic pathways which include neural inputs to the rostral ventrolateral medulla may use AT1 receptors and play a role in the function of sympathetic pathways maintaining arterial pressure.
  相似文献   
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